First of all, 30ma seems a little high for a yellow LED. I'm used to 20ma for yellows, higher for blue and white, although it will work higher (and be brighter). Since it's just your computer, it won't matter if they burn out in 3 years rather then 10.

Second, since they are series, the total current draw for both is 30ma, not 60ma.

It doesn't matter whether you put the resistor before or after the LEDs.

Originally posted by Joe Ross First of all, 30ma seems a little high for a yellow LED. I'm used to 20ma for yellows, higher for blue and white, although it will work higher (and be brighter). Since it's just your computer, it won't matter if they burn out in 3 years rather then 10.

Yeah, I realized after I posted it that the specs I listed were for a different LED - not the one I linked to.

Quote:

Originally posted by Joe Ross Second, since they are series, the total current draw for both is 30ma, not 60ma.

3 weeks out of school and you start to mix up your physics already. whoops!

Anyways, fixing that mistake, that means my resister should be a 280ohm?

Super,
Here's a couple of quick steps and some electrical info. LED's can be considered to have 2 volt drops when forward biased and current in series circuits remains the same throughout. So you do not have 60 ma total. If they are high brightness LED you might have 30ma but 20ma is more the standard. So for calculations....
12v - 2(2v) = 8 volts (resistor drop)
so
R = 8/.030 = 266 ohms.